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Biomedical subjects

R Mattioli

Publications and source records attributed to R Mattioli.

At least 19 recordsLinked to original sources
PubMed1998

Prognostic value of myocardial viability in medically treated patients with global left ventricular dysfunction early after an acute uncomplicated myocardial infarction: a dobutamine stress echocardiographic study.

BACKGROUND: Residual viable myocardium identified by dobutamine stress after myocardial infarction may act as an unstable substrate for further events such as subsequent angina and reinfarction. However, in patients with severe global left ventricular dysfunction, viability might be protective rather than detrimental. The aim of this study was to assess the impact on survival of echocardiographically detected viability in medically treated patients with global left ventricular dysfunction evaluated after acute uncomplicated myocardial infarction. METHODS AND RESULTS: The data bank of the large-scale, prospective, multicenter, observational Echo Dobutamine International Cooperative (EDIC) study was interrogated to select 314 medically treated patients (271 men; age, 58+/-9 years) who underwent low-dose (</=10 microg x kg-1 x min-1) dobutamine for the detection of myocardial viability and high-dose dobutamine for the detection of myocardial ischemia (</=40 microg x kg-1 x min-1 with atropine </=1 mg) performed 12+/-6 days after an acute uncomplicated myocardial infarction and showing a moderate to severe resting left ventricular dysfunction (wall motion score index [WMSI] >1.6). Patients were followed up for 9+/-7 months. Low-dose dobutamine stress echocardiography identified myocardial viability in 130 patients (52%). Dobutamine-atropine stress echocardiography was positive for ischemia in 148 patients (47%) and negative in 166 patients (53%). During the follow-up, there were 12 cardiac deaths (3.8% of the total population). With the use of Cox proportional hazards model, delta low-dose WMSI (the variation between rest WMSI and low-dose WMSI) was shown to exert a protective effect by reducing cardiac death by 0.8 for each decrease in WMSI at low-dose dobutamine (coefficient, -0.2; hazard ratio, 0.8; P<0.03); WMSI at peak stress was the best predictor of cardiac death in this set of patients (hazard ratio, 14.9; P<0.0018). CONCLUSIONS: In medically treated patients with severe global left ventricular dysfunction early after acute uncomplicated myocardial infarction, the presence of myocardial viability identified as inotropic reserve after low-dose dobutamine is associated with a higher probability of survival. The higher the number of segments showing improvement of function, the better the impact is of myocardial viability on survival. The presence of inducible ischemia in this set of patients is the best predictor of cardiac death.

Aged↗
PubMed1998

Conditioned place-preference analysis in the goldfish with the H1 histamine antagonist chlorpheniramine.

The aim of this study was to investigate whether the histamine H1-receptor blocker, chlorpheniramine (CPA), has a reinforcing effect in goldfish. We used a place-preference procedure in an aquarium with two chambers colored black and white. On day 1, the animals were placed in the test chamber for 10 min for habituation. On day 2, they were placed in the start compartment for 30 s, the sliding doors were opened, and the time spent in each compartment was recorded over the 10 min to determine the natural compartment preference for each animal. On day 3, they were injected either with 0.1, 0.4, 1.0, or 4.0 mg/kg of CPA or only with vehicle and placed in the less preferred compartment for 25 min. On day 4, the animals were placed in the start compartment and the time spent in each compartment during the 10-min test period was recorded again. The groups treated with 1.0 and 4.0 mg/kg of CPA, spent significantly more time in the compartment in which they experienced the drug effect than the group treated with vehicle. On the other hand, the group treated with 0.4 mg/kg spent significantly less time in the drug-paired compartment. The results indicate a biphasic effect of CPA. Considering that there is evidence that low doses of CPA can also block H3-receptors, we suggest that in goldfish the histaminergic neural system has an inhibitory role in the reinforcing process.

Analysis of Variance↗
PubMed1998

Effect of sample volume location on Doppler-derived transmitral inflow velocity values in 288 normal subjects 20 to 80 years old: an echocardiographic, two-dimensional color Doppler cooperative study.

The aims of the study were to evaluate in a population of 288 normal subjects 20 to 80 years old (1) the normal values of the indexes of the mitral flow velocity pattern measured either at the tips of the mitral leaflets or at the annulus; (2) whether there was a significant difference between the values obtained at the tips compared with those measured at the mitral annulus; (3) the correlation with aging between the indexes measured in the two different positions; and (4) whether certain physiological variables have different effects on diastolic function measured in the two different positions. The highest values were always measured at the tips of the mitral leaflets (p < 0.05); only atrial filling fraction, E acceleration time, and E deceleration velocity had higher values when measured at the level of the annulus (p < 0.05). The A-wave peak velocity had the same mean value when measured at both the tips and at the annulus. A significant difference in the correlation between parameters measured at the tips of the mitral leaflets with age and at the annulus (with age) was observed for the following parameters: (1) peak E velocity, E integral, total integral and E acceleration showed better correlation with age when measured at the annulus (p < 0.02); (2) peak A velocity and A integral showed better correlation with age when measured at the tips of the mitral leaflets (p < 0.001). Multivariate analysis showed that age was the variable that had the most influence on diastolic function parameters; heart rate had less influence on the diastolic function indexes.

Adult↗
PubMed1997

Substance P facilitates memory in goldfish in an appetitively motivated learning task.

The aim of this study was to investigate if the neuropeptide substance P (SP) can improve learning and memory in goldfish (Carassius auratus). Four groups of fish were trained for seven days to find food in one out of two compartments until discrimination was achieved. On the last training day, they were injected (intra-abdominal) with haloperidol or vehicle before the training, and with SP or vehicle immediately after the training session. Each group of fish received either: (1) vehicle+vehicle (n = 18); (2) vehicle + SP, (n = 20, SP 50 mg/kg); (3) haloperidol+ vehicle (n = 15, haloperidol 2 mg/kg); or (4) haloperidol+ SP (n = 14, haloperidol 2 mg/kg, SP 50 mg/kg). Twenty-four hours later, the time spent to find the food was recorded. Reversal training was done for four consecutive days after this post-injection test and the time spent to find the food was recorded again. The results indicate that only the group treated with vehicle + SP needed more time to reach reversal training than control fish (Mann-Whitney U-test, P = 0.0009). It is suggested that SP can enhance memory in fish and that this effect may have a dopaminergic mediation in discrimination learning task.

Animals↗
PubMed1997

Pulmonary venous flow velocity patterns in 143 normal subjects aged 20 to 80 years old. An echo 2D colour Doppler cooperative study.

In order to find out the normal values and to evaluate the effects of age, heart rate, sex, and haemodynamic and standard echocardiographic parameters on pulmonary venous flow velocity obtained by the transthoracic approach. Doppler pulmonary venous flow parameters were measured in 143 healthy subjects aged from 20 to 80 years. Doppler pulmonary venous flow parameters which had the best correlation with age were: the peak velocity of the systolic wave (r = 0.39) and its integral (r = 0.5), the peak velocity of the diastolic wave (r = -0.6) and its integral (r = -0.44); the systolic (r = 0.68) and diastolic fractions (r = -0.68); the systolic/diastolic peak velocity ratio (r = 0.73) and the systolic/diastolic integral ratio (r = 0.7). The atrial reversal wave did not correlate with age; the atrial reversal wave was more difficult and probably less reliable to measure than the systolic and diastolic waves. The correlations of pulmonary venous flow parameters with mitral flow parameters were also examined. This study showed that, in healthy subjects, despite an increase in the early and atrial waves from the annulus to the tips of the mitral leaflets, there is a similar association between pulmonary venous flow and mitral flow measured at the annulus or at the tips of the mitral leaflets. The intra-observer reproducibility of all the pulmonary venous flow parameters considered were found to be excellent. Moderate inter-observer variability was observed for the systolic, diastolic and atrial reversal wave peak velocities and integrals; however, the systolic/diastolic ratio improved the precision of the measurements. Multivariate analysis showed that age is the principal determinant of the Doppler parameters of pulmonary venous flow: heart rate, sex, body surface area, the size of the left atrium in systole and the left ventricular ejection fraction all influence the Doppler parameters of pulmonary venous flow, even if only slightly.

Adult↗
PubMed1997

Corneal geometry reconstruction with the Keratron videokeratographer.

BACKGROUND: Color-coded corneal maps produced by computer-assisted videokeratographers (CAVKs) have become an indispensable tool for clinical understanding of corneal shape. However, Placido-based CAVKs are criticized as theoretically incapable of producing accurate corneal height information. PURPOSE: This paper describes how the Keratron (Optikon 2000, Rome, Italy) integrated design innovations to achieve accuracy and map use previously thought to be unobtainable. METHODS: The Keratron implemented a spherically unbiased surface reconstruction method that yields height, axial power, and instantaneous curvature without derivation of one quantity from another. Processing innovations resulted in sub-micron height accuracy. The Keratron includes axial power, instantaneous curvature, refractive maps, a height map (spherical offset), pupil edge detection, a "move axis" feature, process editing, indices, a contact lens program, and photorefractive keratectomy (PRK) simulation. CONCLUSIONS: The algorithms for surface reconstruction and the design solutions implemented in the Keratron resulted in accurate height, axial power, and instantaneous curvature measurement and valid, clinically useful maps, as well as additional user options and features.

Algorithms↗
PubMed1997

Hypercoagulability and chronic atrial fibrillation: the role of markers of thrombin generation.

BACKGROUND: We have studied 64 patients with congestive heart failure, half of them also with chronic nonvalvular atrial fibrillation (AF). Patients were also stratified according to a history of prior stroke. METHODS: The generation of thrombin was investigated by means of the molecular markers prothrombin fragment 1 + 2 (F1 + 2) and thrombin-antithrombin III complex (TAT), because AF patients may have a hypercoagulable state. There was only a trend toward higher values of TAT and F1 + 2 for AF patients, while subjects with previous stroke (irrespective of AF) had increased levels of the markers of thrombin generation (TAT stroke+ 18.95 +/- 5.15 vs TAT stroke- 8.34 +/- 2.41; F1 + 2 stroke+ 2.22 +/- 0.29 vs F1 + 2 stroke- 1.32 +/- 0.12). The presence of spontaneous echo contrast (SEC) within left atrium was also investigated in 32 AF patients by transesophageal echocardiography. RESULTS: TAT were significantly higher in subjects (n = 11) with SEC (TAT sec+ 37.5 +/- 13.41 vs TAT sec- 8.7 +/- 2.51, p = 0.008). CONCLUSIONS: Finally, when we grouped into 1) those with both AF and stroke, 2) AF alone, 3) stroke alone and 4) sinus rhythm without stroke, levels of F1 + 2 were higher (and marginally higher TAT) in patients with AF and stroke than in those without stroke, revealing that there is a true clotting activation state in these subjects.

Aged↗
PubMed1996

Reinforcing properties of the substance P C-fragment analog DiMe-C7 in Carassius auratus.

The aim of the present study was to investigate whether two substance P (SP) fragments have reinforcing effects in Carassius auratus when the fish were tested in a place-preference experimental model. Fish were placed in a 3-compartment box in which one compartment gives access to two others that are not connected. The time spent in each compartment was recorded for 10 min in order to determine which one was preferred. Twenty-four hours later the fish were given one of the following ip treatments: 1) group VEH (N = 12), injected with teleost saline, 2) group DiMe-C7 (N = 12), injected with 33 micrograms/kg DiMe-C7, and 3) group SP1-7 (N = 12), injected with 167 micrograms/kg SP1-7. Immediately after treatment the fish were kept for 30 min in the compartment that was the least preferred on the day before and this procedure was repeated for 3 days. On the fifth day the fish were retested for 10 min to determine the time spent in each compartment. Two-way analysis of variance with treatments and testing as factors indicated a main effect (P < 0.0025) as well as a testing effect (P < 0.009). The post-hoc Scheffé multiple comparison test indicated that only the DiMe-C7 group presented an increase in the time spent in the paired compartment after treatment. We suggest that the C-terminal fragment of SP has reinforcing effects in Carassius auratus.

Animals↗
PubMed1995

Reinforcing properties of the neuropeptide substance P in Carassius auratus: evidence of dopaminergic system involvement.

The aim of the present study was to investigate whether neuropeptide substance P (SP) has reinforcing effects in Carassius auratus and whether this effect could be related to dopaminergic neurotransmission. For this purpose fishes were put in a three-compartment box in which one compartment gave access to two others that did not directly link. The time spent in each compartment was registered for 10 min to determine a possible preferred compartment. Twenty-four hours later, the fish were given one of the following intraperitoneal treatments: a) Group VEH, injected with the vehicle of substance P; b) Group SP25, injected with SP, 25 micrograms/kg body wt.; c) Group SP50, injected with SP, 50 micrograms/kg; or d) Group HALO, injected with haloperidol (2 mg/kg) 30 min before an injection of SP (50 micrograms/kg). Immediately after the treatment the fish were kept for 30 min in the compartment preferred least the day before. On the next day the fish were retested for 10 min to verify the time spent in each compartment. The results indicate that SP at the dose of 50 micrograms/kg enhanced the time spent on the paired compartment, and that the pretreatment with haloperidol abolished this enhancement. It is suggested that SP has reinforcing effects in C. auratus that may be mediated by the dopaminergic system.

Animals↗
PubMed1995

Repetitive proteins from the flagellar cytoskeleton of African trypanosomes are diagnostically useful antigens.

Trypanosome infection of mammalian hosts leads, within days, to a strong early response against a small, distinct number of parasite proteins. One of these proteins is the variable surface glycoprotein (VSG). Most of the others are apparently non-variable, intracellular trypanosome proteins. Two of these antigens I2 and I17 are now characterized at the molecular level. Both exhibit a highly repetitive amino acid sequence organization, but they show no sequence similarity either to each other or to any other proteins known to date. Preliminary serological analyses indicate that both allow the early, sensitive and specific detection of infections with different species of trypanosomatids, making them interesting candidates for the development of diagnostic tools for trypanosomiasis detection.

Amino Acid Sequence↗
PubMed1993

Mitomycin C, 5fluorouracil and folinic acid in combination with alpha 2b interferon for advanced colorectal cancer.

AIMS AND BACKGROUND: This study was conducted to investigate the activity and toxicity of 5fluorouracil folinic acid+mitomycin C combined with alpha 2b interferon in advanced colorectal cancer based upon recent studies suggesting a possible biochemical modulation of 5fluorouracil by interferon. PATIENTS AND METHODS: Between June 1990 and April 1991 25 previously untreated patients with advanced colorectal carcinoma were treated with mitomycin C 10 mg/m2 iv bolus on day 1, 5fluorouracil 375 mg/m2 on days 1 to 4 and folinic acid 200 mg/m2 on days 1 to 4 every 4 weeks, combined with alpha 2b interferon 3 million U day continuously. RESPONSE: Of the 25 patients entered into the study, 20 were evaluable for response as 5 patients withdrew due to toxicity (grade 3-4 thrombocytopenia in 4 cases and fatigue in 1). No complete response was recorded, 6 patients had partial remission (30%; 95% confidence interval, 10% to 50%), 4 experienced no change and 10 showed progressive disease. The toxicity of this regimen was significant, particularly myelosuppression. CONCLUSIONS: This combination showed a significant toxicity and low response rate compared with other 5fluorouracil based regimens in advanced colorectal cancer.

Aged↗
PubMed1993

Peripherally administered substance P affects extracellular dopamine concentrations in the neostriatum but not in the nucleus accumbens under anesthesia.

The in situ microdialysis technique was used in urethane-anesthetized rats to monitor changes in the extracellular concentrations of dopamine and its metabolites in neostriatum and nucleus accumbens after the peripheral administration of substance P (50 or 250 micrograms/kg, IP). Four to five hours after urethane anesthesia a decrease of extracellular dopamine and its metabolites was observed which continued in the nucleus accumbens in the following 3 h. The administration of substance P induced a decrease in extracellular concentration of dopamine in neostriatum. This neurochemical change after substance P was not accompanied by parallel alterations in extracellular concentrations of dopamine metabolites. No effects of substance P were observed on dopamine or its metabolites in nucleus accumbens. These data are discussed in relation with the contrasting effects of substance P on awake rats and the possible changes in striatal dopamine activity induced by anesthetics.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1993

Plasma predeposit: the role of productive plasmapheresis.

At the Rizzoli Orthopaedic Institute, as part of our autotransfusion program, we have recently had the possibility to introduce plasma predeposit by means of productive plasmapheresis in patients undergoing major orthopaedic surgery, in which bleeding more than 50-60% of circulating blood mass was expected and so a greater quantity of plasma compared to red blood cells was considered necessary. Red cells and fresh frozen plasma predeposits and perioperative blood recovery was sufficient to cover transfusional needs. In our opinion, plasma predepositing by plasmapheresis is indicated in patients with anaemia, cardiopathy and/or vasculopathy, minute constitution.

Adult↗
PubMed1993

[Myocardial response to ischemia produced by repeated coronary occlusions: an experimental study].

BACKGROUND: The fact that brief repeated episodes of ischemia may induce prolonged functional depression of the left ventricle is still a matter of debate. During an angioplasty several brief (20-90 sec) coronary occlusions are performed, with the potential risk of inducing myocardial jeopardy. METHODS: We performed 4 repeated LAD occlusions in 7 open chest pigs under general anesthesia and controlled ventilation. The following parameters were evaluated: mean systemic arterial pressure (MAP), left ventricular peak systolic pressure (LVPSP), heart rate (HR), and peak negative and positive dP/dt (dP/dt- and +). Each parameter was measured in the basal state and every 4 sec, in the expiratory phase, during the coronary occlusion, the first min and after 10 min of reperfusion. The percent change from control values for each parameter was also calculated and, by means of the ANOVA test, the differences among the 4 consecutive occlusions for each parameter were tested. RESULTS: The results showed that: 1) coronary occlusions significantly depressed dP/dt + and -, MAP and LVPSP, while HR did not change; 2) each variable returned to control values within 1 min of reperfusion; 3) the response to ischemia (percent change) was the same in each of the 4 consecutive occlusions for all parameters at every recording time. CONCLUSIONS: We can conclude that: 1) each experimental coronary occlusion induces a depression of myocardial function that is reversible in 1 min of reperfusion; 2) four repeated 2 minutes coronary occlusions do not induce cumulative effects on myocardial response to ischemia.

Analysis of Variance↗
PubMed1992

Effects of substance P on extracellular dopamine in neostriatum and nucleus accumbens.

Microdialysis was used to monitor changes in dopamine release in the neostriatum and nucleus accumbens after peripheral administration of substance P in freely moving rats. Substance P in a dose of 50 micrograms/kg produced a steady moderate increase in dopamine levels in the neostriatum, which persisted for at least 5 h. In contrast, a dose of 250 micrograms/kg caused an acute increase in dopamine levels in the nucleus accumbens, which lasted about 2 h. These data suggest that the peripheral administration of substance P can influence dopamine release in mesolimbic and mesostriatal terminals.

3,4-Dihydroxyphenylacetic Acid↗